Photosensitive screen drum for electrographic apparatuses

Abstract

A photosensitive screen drum for electrographic apparatuses. The photosensitive screen drum comprises a photosensitive screen wound around a cylindrical supporting body composed of a pair of insulating discs rotatably mounted on a fixed shaft and spaced apart from each other and an electric conductive supporting member formed into an arcuate segment and connecting the insulating discs. The electric conductive supporting member is provided at least its inner surface with an insulating coating.

What is claimed is: 
     
       1. A photosensitive screen drum for electrographic apparatuses comprising: a casing; a fixed shaft secured to said casing; a cylindrical supporting body composed of a pair of insulating discs rotatably mounted on said fixed shaft and spaced apart from each other, and an electrically conductive supporting member secured at its both ends to said insulating discs, said electrically conductive supporting member being formed into an arcuate segment having at least an inner surface thereof with an insulating coating formed thereon; and a photosensitive screen wound around said cylindrical supporting body and secured at both ends thereto; said supporting member being formed of the same material and having the same thermal expansion coefficient as said photosensitive screen. 
     
     
       2. A photosensitive screen drum for electrographic apparatuses as claimed in claim 1, wherein: said electrically conductive supporting member formed into an arcuate segment is provided at both ends with tapped holes threadedly engageable with bolts extending through said insulating disc and having said insulating coating at its inner surface. 
     
     
       3. A photosensitive screen drum for electrographic apparatuses as claimed in claim 2, wherein: said arcuate segment is provided with said insulating coating along its overall surface. 
     
     
       4. A photosensitive screen drum for electrographic apparatuses as claimed in claim 1, wherein: said photosensitive screen is formed into a flat rectangular photosensitive screen secured at its four sides to a rectangular frame, said frame with said screen being wound around said cylindrical supporting body.